In case of a DSM Deallocate (unmap) with multiple ranges, individual
bdev IOs are submitted for each range. If the bdev IO cannot be
allocated, the request is queued on io_wait_queue; however previously
submitted ranges may complete before memory is available for the next
range. In such a case, the completion callback will free unmap_ctx,
while the request is still queued for memory - causing a segfault
when the request is dequeued. To fix, introduce a new field tracking
the unmap ranges, and make sure the count is nonzero when the request
is queued for memory.
Signed-off-by: Yair Elharrar <yair@excelero.com>
Change-Id: Ifcac018f14af5ca408c7793ca9543c1e2d63b777
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/447542
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>